Yellowish tint on MVS output through supergun

Hi all,
I just got my MVS yesterday and when I attached it to my supergun and started it up in test mode, I noticed that the text looked yellow. RGB test confirms that white is yellowish and the effect persists in-game as well. The board looks pretty good for its age and I didn't notice any signs of capacitors leaking. Sometimes, it will flicker briefly to white but then the yellow tint returns. Any ideas on where to start?

Does your supergun have rgb adjustment knobs? You probably just need to mess with those to get the color to look right.

Thanks for the reply. Not externally at least. I'll check with the guy who built the supergun to see if maybe there are some internal pots I can adjust.

It's possible that they could be inside the supergun.

Nothing inside the supergun unfortunately, I took it apart to check. I realized I could change the RGB offsets on the OSSC but I'm a little stuck on where to go. I thought it'd be easier to take a screenshot and change the levels in photoshop, then apply that same transform to the levels on the OSSC. But I just can't work out the color transformation I need. I'll post the original screenshot. What's getting me is, the "CREDIT 00" is perfectly white but the rest is way off.
View attachment Untitled.bmp

LamDierg said:

Nothing inside the supergun unfortunately, I took it apart to check. I realized I could change the RGB offsets on the OSSC but I'm a little stuck on where to go. I thought it'd be easier to take a screenshot and change the levels in photoshop, then apply that same transform to the levels on the OSSC. But I just can't work out the color transformation I need. I'll post the original screenshot. What's getting me is, the "CREDIT 00" is perfectly white but the rest is way off.

Click to expand...

Actually that's pretty weird that Credit 00 is white but other stuff isn't. I assume you have tested with various games. Do you have a way to test the MVS without using the OSSC/Supergun?

K' looks sexy blonde tho :-P

Yeah, it's really weird. Unfortunately, I'm just getting into MVS and this is the only cartridge I have. I thought I was going to be smart and run KoF 99 in final burn alpha, grab a screenshot from it, and compute the RGB offset vs what's coming out of the OSSC. Well, that yielded nothing but confusion. The offsets aren't constant. Heck, in some pixels there's too much blue and in others, too little. Take K's jacket, significantly too much blue. Yet, the borders around the character have way too little. So I don't even see how RGB potentiometers would help. Also, if anyone has any advice on getting rid of the super-inconsistent sync coming from a MV-1fz I'd be eternally grateful. I've followed the settings here: http://junkerhq.net/xrgb/index.php?title=OSSC_potential_incompatibilities but even maxing out Hsync tolerance and H-PLL pre and post coast still results in sync drops.

It's worth noting too that the yellow tint is also present in the hardware test. I think we can probably rule out the game itself.

Pretty sure this is one of my customers. On the case now- gonna see if i can recreate this. I havent encountered this sort of thing with the ossc before.

Also- lam- got your last email i'll hit you back when i get home this evening and had some time to mess with this.

Post a pic of the color bars in the hardware test on the MVS. That would help.

So, earlier when I said the board looked OK, I was meaning no signs of corrosion etc. However, I found board scans of the FZ for comparison and oh boy. Some idiot replaced 6 of the surface-mount resistors near the edge connector with through-hole versions that don't even have the correct resistance. Oh, and R25 is gone completely, hopefully that wasn't important. They also added a through-hole resistor in parallel to the sync resistor for some reason. Anyway, I just got a 1B that I'm going to use until I find the motivation and components to fix the FZ. I appreciate all of the replies.